The invention relates generally to making of adhesive from plant materials and more particularly to the making of adhesive from liquefaction oil produced from lignocellulosic plant material or biomass.
In the manufacture of plywood successive layers of wood may be bonded together with phenol-formaldehyde adhesives. Because the production of petroleum-base phenol may be expensive, there have been various efforts to at least partially substitute the phenol with woodbased products or extracts such as tannins or bark extracts.
Gallivan in U.S. Pat. Nos. 4,209,647 and 4,223,465 discloses a method for recovering a phenolic fraction from oil obtained by pyrolysis of lignocellulosic materials and the subsequent use of that fraction in making phenol-formaldehyde resin. However, this process suffers the disadvantage of requiring pyrolysis oils which are usually formed at a higher temperature and which require a dry feedstock.
The inventors have discovered a process for making phenol-formaldehyde type resins from liquefaction oils. Liquefaction oils are also derived from lignocellulosic plant materials or biomass, but are produced at lower temperatures, at higher pressures, and in the presence of water.
It is accordingly, an object of this invention to provide a method for producing a readily available substitute for phenol-formaldehyde resins.
It is a further object of this invention to produce an adhesive from oils produced from lignocellulosic plant materials under liquefaction conditions in the presence of water.
Other objects, advantages, and novel features of the invention will be apparent to those of ordinary skill in the art upon examination of the following detailed description of a preferred embodiment of the invention and the accompanying drawings.